Concrete working tool



March 26, 1963 w. s. HAIVALA CONCRETE WORKING TOOL Filed Aug. 2. 1960 INVEIYTOR. Wag ham ,ih apaala,

HTTOR NEYS United States Patent 3,082,460 CONCRETE WORKING TOOL William S. Haivala, 1716 N. Sabin, Wichita, Kans. Filed Aug. 2, 1960, Ser. No. 46,955 1 Claim. (Cl. 235.4)

This invention relates to tools for forming concrete slabs and in particular an elongated hollow straight edge having a vertically disposed longitudinally positioned web extended from the center of the base, upwardly through the upper panel, and having a handle pivotally mounted on the web and supported laterally by diagonally disposed braces extended from the handle to points on the straight edge substantially midway between the point of connection of the handle to the web and the ends of the straight edge, and wherein the tool of the present invention may be used without the braces so as to permit pivotal movement of the handle, or else the tool may be used with the braces thereon when no pivotal action of the handle is desired or required.

The purpose of this invention is to provide an elongated straight edge for checking concrete slab Work in which the straight edge is of light weight and durable construction.

In checking concrete slab work for floor and roof slabs and for sidewalk and street paving it has been the practice in former years to use straight boards which are short lived because of war-page and they were clumsy and hard to use. Steel bars also have been used for this purpose, but it is extremely heavy and require extra labor on the job. After experiencing difficulty with these various materials, square metal tubing has been used successfully. However, because straight edges for this use are relatively long, and because they are often used to actually drag excess concrete from a slab, it has been found necessary to combine light weight with the necessary strength to provide an absolutely straight checking tool from job to job.

With this thought in mind this invention contemplates a straight edge for checking concrete slab work in which the leading surface extends outwardly in the form of a V whereby an inclined surface extends upwardly from the leading edge of the base and merges into a surface sloping downward from the upper panel of the hollow section of the straight edge, and wherein the blade is reinforced by a vertically disposed web extended upwardly through the tube forming the body of the straight edge.

The object of this invention is, therefore, to provide a straight edge for checking concrete slab work in which the leading edge is V shaped so that it has the strength and rigidity necessary to drag excess concrete from high spots on a slab and still remain straight.

Another object of the invention is to provide a straight edge for concrete construction in which the straight edge is of light weight so that it may be handled by a single operator.

A further object of the invention is to provide a straight edge for checking concrete slab work in which the straight edge is of simple and economical construction.

With these and other objects and advantages in view the invention embodies an elongated straight edge having an inclined surface extended upwardly from the leading edge with a vertical reinforcing web extended from the base through the upper portion, and a handle attached to the web and supported by diagonally positioned braces extended from the handle to the straight edge.

Other features and advantages of the invention will appear from the following description taken in connection with the drawings, wherein:

FIGURE 1 is a plan view of the improved straight edge of the present invention.

3,082,460 Patented Mar. 26, 1963 FIGURE 2 is an end elevational view of the straight edge with part of the handle broken away and with the braces removed.

FIGURE 3 is a rear elevational view of the straight edge taken on line 33 of FIGURE 1, with parts broken away, and with parts shown in section.

FIGURE 4 is a cross section through the straight taken on line 44 of FIGURE 3, with the parts shown on an enlarged scale, and with the handle assembly omitted.

FIGURE 5 is a perspective view of the straight edge, also with the handle and associated parts omitted.

Referring now to the drawing wherein like reference characters denote corresponding parts, the improved straight edge of this invention includes a channel-shaped body with a V-shaped leading side and having a vertically disposed web extending upwardly through the body. The channel-shaped body includes a base 10, a rear wall 11, and an upper panel 12, and the V-shaped leading side includes a lower inclined wall 13 and an upper sloping wall 14. The vertically disposed web 15 extends from a point 1-6 on the base, and to a point 17 of the upper panel 12 to a point 18. The body is preferably made of magnesium although other materials may be used.

The straight edge is provided with a handle 19 having an eye 20 extended from a socket 21 threaded on a stud 22 extended from the end of the handle, and the eye is pivotally connected by a bolt 23 to a tongue 24 of a base 25. The base 25 is secured to the web 15 by suitable securing elements such as rivets 26.

The handle is supported laterally by braces 27 and 28 which are connected to the handle 'by a clamp 29. Outer ends of the braces are secured in the clamp by bolts 30 and 31 and flattened inner ends 32 and 33 are secured to the rear panel 11 by screws 34 and 35. The handle 19 may readily be made to pivot with respect to the straight edge by removing the bolts 30 and 31 from the clamp 29, to detach the braces from the handle 19. If necessary, the screws 34 and 35 may also be removed. When the handle 19 is used without the braces 27 and 28, the V-shaped leading side or edge may be pointed downwardly so as to scrape or level unset concrete, with the web 15 overlying the adjacent portion of the handle 19. Ordinarily, with the braces 27 and 28 attached, the straight edge is used with the base 10 in engagement with the surface of the concrete and with the V-shaped leading side or edge pushed forwardly over the concrete to smooth same.

Although the straight edge or blade may be ten or twelve feet long and one and one-half inches high, it will be understood that the blade may be of any suitable length or height.

In use the straight edge is moved forwardly with the inclined leading surface crowding concrete in under the base whereby a smooth even surface is obtained.

It will be understood that modifications, Within the scope of the appended claims, may be made in the design and arrangement of the part swit-hou-t departing from the spirit of the invention.

What is claimed is:

'In a straight edge tool for working concrete, a rectangular shaped body having a base, arear wall arranged at right angle with respect to said base, an upper panel arranged in spaced parallel relation with respect to said base, said body further including a front wall which is V-shaped in cross section positioned with the vertex extending outwardly from said body and with the side portions thereof inclined to the leading edges of the base and upper panel, a vertically disposed web rising from a point middle-way of the width of said base upwardly to the upper panel and having an extension portion projecting above the upper panel, -a handle pivotally mounted on the Web extension portion and extended rearwardly therefrom, and diagonally disposed braces extended from the handle to said rear wall and connected thereto at points spaced from the point of connection of the handle to the web.

References Cited in the file of this patent UNITED STATES PATENTS Swanson May 18, 1926 Whalen Sept. 2, 1952 Brough Jan. 18, 1955 Levy Jan. 30, 1962 

